Hydraulic speed control for motor vehicles



Oct. 22, 1957 I J. M. SEAY 2,810,461

HYDRAULIC SPEED CONTROL FOR MOTOR VEHICLES Filed Jan. 30, 1957 INVENTOR. JEsss M. 854) fiwmfiwa HYDRAULEC SPEED CONTROL FOR MOTOR VEHICLES Jesse M. Seay, Detroit, Mich.

Application January 30, 1957, Serial No. 637,107

Claims. (Cl. 192-3) This invention relates to a speed control for a vehicle, and more particularly to a hydraulically operated mechanism for regulating the carburetor control valve.

One of the inconveniences encountered with the conventional accelerator pedal used in motor vehicles is the requirement that the drivers foot must be in constant engagement with the pedal, which, on long trips becomes tiring.

The present invention provides a novel means for operating the carburetor valve control lever which eliminates the use of the accelerator pedal.

It is the object of the present invention to provide a hydraulic mechanism for operating the carburetor control lever, together with a remote manual speed control upon the vehicle dashboard for regulating said hydraulic mechanism.

It is another object of this invention to utilize the conventional lubricating oil pressure means of the vehicle engine for delivering fluid under pressure to said hydraulic mechanism.

It is the further object of the present invention to provide on the vehicle dashboard a dial indicator control pointer for setting the control mechanism to the desired speed.

It is the further object of this invention to provide a bypass valve structure in the fluid system for the carburetor control whereby the fluid supply is temporarily interrupted on application of the vehicles brakes.

It is still the further object herein to provide for increased control movement of the hydraulic control mechanism upon the temporary falling off of the engine vacuum as where the engine encounters an increased load which might be due to an incline in the roadway or a desire for acceleration.

These and other objects will be seen from the following specification and claims in conjunction with the appended drawing in which:

Fig. 1 is a fragmentary side elevational view of a vehicle engine and portions of the associated vehicle chassis.

Fig. 2 is an elevational section on an enlarged scale of the brake pedal operated bypass valve.

Fig. 3 is an elevational section on an enlarged scale of the fluid control mechanism shown in Fig. 1.

Fig. 4 is a section taken on line 44 of Fig. 1, but on an enlarged scale.

Referring to the drawing, a portion of the vehicle chassis is shown at 11, Fig. 1 terminating in the conventional fire wall 12, floorboard 13 and dashboard 16, and the associated fragmentary brake pedal 14 with its supporting arm 15, all being of conventional construction.

The vehicle engine 17 has a carburetor 18 with fuel supply conduit 19 fragmentarily shown, and above the carburetor a conventional air intake 20. There is also shown the fuel intake manifold 21 associated with said carburetor, and also the exhaust manifold 22 and adjacent thereto the cylinder head 23 from which engine oil is delivered under pressure through conduit 24.

This oil is delivered to the emergency cutofi valve 25 hereafter referred to as a bypass valve which has a piston it States Patent 31 therein and rod 26 arranged with respect to the said brake pedal and the associated leaf spring 27 whereby application of the vehicle brake will move the bypass valve piston 31 from the normal position of operation shown in Fig. 2, against the action of coiled spring 37, cutting oif the flow of pressure fluid.

Normally circulating pressure fluid leaves bypass valve through conduit 28 for direction to housing 29 for the hydraulic control mechanism which regulates the longitudinal adjustment of rod 42 connected at its outer end to the carburetor valve control lever 43.

Exhaust fluid from control mechanism 29 returns to the fluid pressure source within cylinder head 23 by means of conduit 30.

Said bypass valve has a pair of radial passages 32 and 35 interconnected by the axial passage 34. Pressure fluid from conduit 24 passes from intake port 33 into passage 32, through passage 34, out passage 35, and through outlet port 36 connecting conduit 28.

Referring now to Fig. 3 there is shown on an enlarged scale the heart of the present hydraulic control mechanism generally indicated at 29, and which includes inlet 38 connected by conduit 28, and which provides pressure fluid to the inlet bore 39 and the movable piston 41 therein.

Piston rod 42 extends through sealing cap and is connected, as shown in Fig. l, with the carburetor valve control lever 43. Accordingly longitudinal adjustment of piston 41 against the action of coiled spring 44 will determine the adjustment of the conventional butterfly valve in the carburetor, and the resulting speed of operation of the vehicle engine.

Within housing 29 there is an outlet bore 46 parallel to bore 39, and interconnecting said bores are a series of parallel spaced transverse bleed passages generally indicated at 45. Additional circled numerals identify the successive bleed passages corresponding to the desired vehicle speed i. e., 25, 30, 35, 40, 45, etc., miles per hour.

Longitudinally adjustable piston 49 is manually set from the remote control 54 on the vehicle dashboard hereafter described, and includes the axial passage 48 which extends to one end of the piston 49, the other end of said passage terminating in the radial bore 47.

In operation, the piston 49 has been manually set so that bore 47 registers with the bleed passage corresponding to miles per hour. This means that upon application of pressure fluid to bore 39, piston 41 will be moved longitudinally controlling the vehicle carburetor until the bleed passage corresponding to the circled 45 numeral is uncovered. At that point piston 41 will stop and pressure fluid passes through said bleed passage and through pas sages 47 and 48 into bore 46 and through the outlet 57 and the outlet fitting 58 to the exhaust conduit 30 for return to the pressure fluid source.

Piston rod 50 has a swivel connection with piston 49 by means of a suitable spring biased ball detent 10 which engages within an annular recess formed adjacent the end of rod 50. Said rod terminates in the elongated screw 51 which threadedly engages a suitable sealing plug 9 at the end of bore 46, said screw being adapted for longitudinal adjustment on rotation thereof.

For this purpose, there is provided an elongated flexible shaft 51' of polygonal shape in cross section whose outer free end is slidably keyed within a correspondingly shaped slot 8 formed throughout a greater portion of the length of screw 51.

The opposite end of shaft 51' extends through fire wall 12 and into gear box 52 and is connected to a small pinion which is intermeshed with a series of speed up gears connected with the shaft of the manually rotatable pointer 54. As shown in Fig. 4 said pointer includes a manually rotatable knob and indicator 55 mov- 3 able with respect to calibrated disc 56 which has marked thereon a series of numerals corresponding to the speeds 25, 30, 35, 40, etc., miles per hour.

As the distance of movement of pointer. arnr 55v for a S -Inile; per hour change is somewhat limited,-i n; order to provide for a corresponding longitudinal adjustment of piston 49;, it is'necessary to employ the gear box. 52- which. thereby multiplies the rotary movement of shaft 51'. This shaft in turn rotates screw 51 for obtaining. thedesired' adjustment of piston 49.

- Interposed within housing 29 adjacent exhaust outlet 57- there isprovided: an. upright bore 59 for the arcuately adjustable plug valve 60- which has a. transverse passage 69 normally in registry with outlet 57'.

Slight rotation or valve Gil will thus. constrict the flow.- of exhaust fliiidi with the result. that there will be a fluid pressure build-up in bore 39 and additionaladjustment of pistols 41 without further adjustment of piston; 49. This is desirable where the vehicle engine is placed: under increased: load as. in driving on an in cline such as a hill- Rotatable piston rod 61 extends through a suitable closure; seal: 7? and carries a disc 62 at its upper end' eccentrical'ly connected by the elongated arm 63 to piston rod 64 for the piston 65 within housing 66. Coiled spring 67 normally urges piston 65- to the left. Vacuum conduit 68 is connected tocylinder 66 and is also connected to the engine vacuum such as at the engine intake manifold whereby changes in the vacum condition of the engine, such as a falling ofi thereof will permit the spring 67 to become more efiective causing movement to the left of piston 65. This in turn rotates disc 62 and causes a slight constriction of passage 69 with respect to exhaust outlet 57.

As the supply of pressure fluid to bore 39 is unchanged, there is a partial pressure build-up in bore 39 with the result that piston 41 will move to the right of the position shown in Fig. 3'. This causes a further opening of the control valve within the carburetor 1'8 and increased power.

As vacuum in the engine again builds up to normal, it will operate against spring 67 returning piston 65 to the neutral position shown in Fig. 3 relieving the constriction in exhaust passage 57, so that pressure in bore 39 returns to normal, and piston 41 returns to the position shown in Fig. 3.

Bleed passage 70 interconnects the outer ends of bores 39 and 46 so that pressurefluid which has escaped past piston 41' may pass into the exhaust bore 46 and travel through passage 71 and join exhaust outlet 57 through passage 72. This prevents a build up of pressure fluid upon the right end of bore 39. An additional exhaust passage 73 connects the left end of bore 39 with said exhaust passage to furthermore prevent too great a build up of fluid pressure within bore 39.

The maximum increase in power whenever there is a vacuum fall off, is limited to the movement of piston PI past the end of piston 49. After that, additional pressure will bleed fluid through a second bleed passage adjacent the end of piston 49-, and will exhaust through conduits 71 and 72.

Having described my invention, reference should now be had to the claims which follow:

I claim:

1. A speed control for a vehicle having a dashboard and a carburetor valve control lever; an elongated housing having spaced inlet and outlet bores closed at their ends with a series of parallel spaced transverse bleed passages interconnecting said bores, a first piston movable within said inlet bore and having a piston rod projecting from said housing and operatively joined to said lever, spring means in said bore urging said piston in one direction, said. housing having an inlet joining said inlet bore, a source of fluid under pressure connected with said inlet for moving said piston in the opposite direction, a longitudinally adjustable second piston in said outlet bore having an axial conduit extending to one end of said second piston and intermediate the ends of said piston a connecting radial passage adapted for selective registry for one of said bleed passages, said housing having an outlet joining said outlet bore for returning pressure fluid to said source, a longitudinally adjustable rod connected. with said second piston and projecting from said housing, and a manually operable remote control on said dashboard connected with said latter rod, whereby longitudinal adjustments of said second piston control the longitudinal pressure fluid operated adjustment of said first piston.

2'. The speed control of claim 1, said longitudinally adjustable rod for said second piston having a threaded means engaging said housing, said remote control including a flexible shaft. of polygonal cross section slidably, engaging said rodin driving relation.

3'. The speed control of claim I, said longitudinally adjustable rod for said second piston having a threaded means engaging said housing, said remote control in cluding afiexible shaft of polygonal cross section slidably engaging said rod in driving relation, a speed designating dial on said dashboard, a manually rotatable pointer'on said dial; and intermeshing, gear means interconnecting said pointer and said flexible shaft.

41 The speed control of claim 1, a plug valve in said housing having a transverse passage normally interposed in said fluid outlet and rotatable for partially constrictingsa-id outlet, a cylinder containing a movable piston and rod eccentrically joined to said plug valve, spring means urging said' piston in one direction, a conduit con necting said cylinder to the vehicle engine vacuum for moving said piston in the opposite direction whereby upon a falling off of said vacuum said outlet will be partially constricted providing additional longitudinal movement of said first piston.

5. The speed control of claim 1, said vehicle having, a brake pedal; a fluid bypass valve interposed between said pressure fluid source and said inlet, a spring biased piston having a series of connecting passages for conducting pressure fluid through said bypass valve, and a rod on said piston engageable by said brake pedal for cutting oflfl'ow of pressure fluid on brake application.

References Cited in the file of this patent UNITED STATES PATENTS 2,216,138 Sellers Oct. 1', 1940 2,230,742 Bush Feb. 4, 1941 2,519,510- Smith Aug. 22, 1950 2,671,542 Robnett: Mar. 9, 1954 2,693,711 Kelbel et 3.1. Nov. 9, 1954 

